git.mutantstargoat.com Git - dosdemo/blob - src/screen.c

   1 #include <stdio.h>
   2 #include <stdlib.h>
   3 #include <string.h>
   4 #include <assert.h>
   5 #include "screen.h"
   6 #include "demo.h"
   7
   8 struct screen *tunnel_screen(void);
   9 struct screen *fract_screen(void);
  10 struct screen *grise_screen(void);
  11
  12 #define NUM_SCR 32
  13 static struct screen *scr[NUM_SCR];
  14 static int num_screens;
  15
  16 static struct screen *cur, *prev, *next;
  17 static long trans_start, trans_dur;
  18
  19 int scr_init(void)
  20 {
  21         int i, idx = 0;
  22
  23         if(!(scr[idx++] = tunnel_screen())) {
  24                 return -1;
  25         }
  26         if(!(scr[idx++] = fract_screen())) {
  27                 return -1;
  28         }
  29         if (!(scr[idx++] = grise_screen())) {
  30                 return -1;
  31         }
  32         num_screens = idx;
  33
  34         assert(num_screens <= NUM_SCR);
  35
  36         for(i=0; i<num_screens; i++) {
  37                 int r;
  38                 r = scr[i]->init();
  39                 if(r == -1) {
  40                         return -1;
  41                 }
  42
  43                 /* Make the effect run first if it returns "CAFE" from ins init() */
  44                 if (r == 0xCAFE) {
  45                         struct screen *tmp;
  46                         tmp = scr[i];
  47                         scr[i] = scr[0];
  48                         scr[0] = tmp;
  49                         printf("*** Screen %s displayed out of order ***\n", scr[0]->name);
  50                 }
  51         }
  52         return 0;
  53 }
  54
  55 void scr_shutdown(void)
  56 {
  57         int i;
  58         for(i=0; i<num_screens; i++) {
  59                 scr[i]->shutdown();
  60         }
  61 }
  62
  63 void scr_update(void)
  64 {
  65         if(prev) {      /* we're in the middle of a transition */
  66                 long interval = time_msec - trans_start;
  67                 if(interval >= trans_dur) {
  68                         if(next->start) {
  69                                 next->start(trans_dur);
  70                         }
  71                         prev = 0;
  72                         cur = next;
  73                         next = 0;
  74                 }
  75         }
  76 }
  77
  78 void scr_draw(void)
  79 {
  80         if(cur) cur->draw();
  81 }
  82
  83 struct screen *scr_lookup(const char *name)
  84 {
  85         int i;
  86         for(i=0; i<num_screens; i++) {
  87                 if(strcmp(scr[i]->name, name) == 0) {
  88                         return scr[i];
  89                 }
  90         }
  91         return 0;
  92 }
  93
  94 struct screen *scr_screen(int idx)
  95 {
  96         return scr[idx];
  97 }
  98
  99 int scr_num_screens(void)
 100 {
 101         return num_screens;
 102 }
 103
 104 int scr_change(struct screen *s, long trans_time)
 105 {
 106         if(!s) return -1;
 107         if(s == cur) return 0;
 108
 109         if(trans_time) {
 110                 trans_dur = trans_time / 2;     /* half for each part transition out then in */
 111                 trans_start = time_msec;
 112         } else {
 113                 trans_dur = 0;
 114         }
 115
 116         if(cur) {
 117                 if(cur->stop) {
 118                         cur->stop(trans_dur);
 119                 }
 120
 121                 prev = cur;
 122                 next = s;
 123         } else {
 124                 if(s->start) {
 125                         s->start(trans_dur);
 126                 }
 127
 128                 cur = s;
 129                 prev = 0;
 130         }
 131         return 0;
 132 }